Refurbishing an old VHF antenna?

[GTom]

Does Refurbishing an old VHF antenna make any sense?

I am renewing my VHF and adding AIS to the system. The old RG58 cable I want to get rid of is integrated in the antenna.

The unit is a stainless whip from Communication Aerials, Westbury. The idea is to add a direct SO-259 to the antenna base and remove the old cable completely.

[IslandInfedel]

Unless it’s a HUGE antenna, no.

Refurb a old antenna that’s been in spray, sun, bird crap, etc for decades? Why and what’s your time worth?


Cable
https://www.amazon.com/MPD-Digital-R.../dp/B00ZNXURTI

Antenna
https://www.amazon.com/Shakespeare-3.../dp/B0017YANN2

If you’re using one antenna for both VHF & AIS, be sure to get a splitter
https://www.westmarine.com/buy/simra...tter--17982596

[Jammer]

Antennas are wear items that require periodic replacement.

[Brian.D]

Take on this project with the intent of "I'm at sea and have no other means of communications". In other words, sure, why not, as long as you can gain something from this project. For example, you want to see what is really inside that coil, or look to see what part is most likely to corrode first.

I'd do it just to gain knowledge. Treat this part as if it was an integral part of your boat that needs to be repaired as some point.

[Lake-Effect]

A decent masthead VHF antenna is not that expensive. I would put in a new VHF antenna with your new cable. Then I'd take the old antenna plus as much of the original RG58 as you want to keep, put a connecter on the end, and have someone test this with a VSWR meter, and if it's still good, keep it as a spare or emergency VHF antenna.

[GTom]

It's not really about the price, just the learning, what's inside a 1/2 wave antenna and where to solder what. Actually if the internals allow, I'd solder an rg213 directly in place of the rg58.

[CarinaPDX]

I think the importance of having reliable VHF communications trumps everything else. Buy a new antenna, preferably one with a connector at the base, and consider replacing the coax at the same time (at least do an SWR test). If you like repair/modify the old antenna for interest and amusement but I wouldn't use it as the primary antenna.

While many cruisers seem to be happy with sharing the VHF antenna with the AIS I do not like that approach. The cost of a separate antenna and coax isn't much more, if at all, than the splitter. My communications antenna is at the masthead and the AIS is mounted on the radar mast aft. Simple and reliable. Also, the AIS antenna could be used for communications in an emergency.

Greg

[ka4wja]

GTom,
1) I understand the desire to learn....But...

Originally Posted by GTom

It's not really about the price, just the learning, what's inside a 1/2 wave antenna and where to solder what. Actually if the internals allow, I'd solder an rg213 directly in place of the rg58.

But, I'm firmly with Lake Effect and Greg (CarinaPDX) here!!

And, btw...you're going to find soldering RG-213 to / inside-of that antenna to very difficult...and not recommended!
The stiffness / unwieldy and large bend radius of RG-213, combined with the rather tight space, etc. will make for a poor-reliability connection, if you can even manage it at all....

If you desire to save this antenna for "back-up" / spare, then either replace / solder RG-58 or RG-8x...or secure / mount / solder a SO-239 directly to it....please do not attempt to solder RG-213!
(ever wonder why antennas have connectors on them, or simply RG-8x or RG-58 attached? 'cuz that's what works...

Originally Posted by Lake-Effect

A decent masthead VHF antenna is not that expensive. I would put in a new VHF antenna with your new cable. Then I'd take the old antenna plus as much of the original RG58 as you want to keep, put a connecter on the end, and have someone test this with a VSWR meter, and if it's still good, keep it as a spare or emergency VHF antenna.

Originally Posted by CarinaPDX

I think the importance of having reliable VHF communications trumps everything else. Buy a new antenna, preferably one with a connector at the base, and consider replacing the coax at the same time (at least do an SWR test). If you like repair/modify the old antenna for interest and amusement but I wouldn't use it as the primary antenna.

I'm going to quote (and edit some of it) myself here (from just an hour ago)....

Last month you asked about VHF antennas, and I thought we pointed you in the right direction?
I understand that you are not in the USA, but rather in the UK, so while a particular Shakespeare antenna might not be as easily available, I do recommend you look....or perhaps Glomex? (or Manta, or GAM, etc.)

Did you not find a Shakespeare? or Glomex RA109??
http://www.glomex.us/portfolio-items...c-vhf-antenna/

https://www.amazon.co.uk/Spartechnik...ct_top?ie=UTF8

Originally Posted by ka4wja

Tmacmi,
1) You've been given some good advice here to replace your damaged antenna with a 3' SS whip, and directly connecting it to your coax going into your mast (not needing a short coax jumper), and weather-proofing this connection....

(Now, I also recommend replacing your whole old run of coax, from masthead all the way to your radio, including any bilge/cabin connections....and, yes I also recommend buying your coax from DX Engineering, etc....but, if that isn't possible at the moment, simply replacing your antenna is okay.)


But, please choose your antenna wisely...
The Shakespeare 5215-AIS, or simply the Shakespeare 5215 Classic, are what I recommend...
https://shakespeare-ce.com/marine/product/5215-ais-with-vhf-squatty-body-antenna/

https://shakespeare-ce.com/marine/product/5215-classic-vhf-squatty-body-antenna-copy/


Over the years, my traditional recommendation of the venerable 5215 (which is still a good choice) now has been superseded by the 5215-AIS (which is the same antenna, adjusted/tuned to cover the whole VHF Marine Band, including the AIS frequencies at the top of the VHF Marine Band)...these are basically the same antenna design....designed specifically for masthead installations.

https://shakespeare-ce.com/marine/product/5215-classic-vhf-squatty-body-antenna-copy/

https://www.defender.com/product.jsp?id=70959


https://shakespeare-ce.com/marine/product/5215-ais-with-vhf-squatty-body-antenna/

https://www.defender.com/product.jsp?id=1143635



I do hope this helps.

Fair winds

John


P.S. To show some weather-proofing, here are pics of both of my 3' Shakespeare SS whip antennas....one at masthead (primary VHF and AIS antenna); and one on the stern (secondary/back-up VHF and AIS antenna)

2) I though we already dealt with this last month?
https://www.cruisersforum.com/forums...-235427-2.html




I do hope this helps...

Fair wind

John

[CarinaPDX]

My favorite is the Glomex 3dB with a gorgeous tapered stainless whip and connector for a PL-259 in the base, also used to mount on an L-bracket. https://www.glomex.us/portfolio-item...c-vhf-antenna/ . Mine has a very low SWR. I have had other good antennae, but this one is really superior.

Greg

[Edit: Italian company, available in Europe and the US.]

[IslandInfedel]

Originally Posted by ka4wja

GTom,
1) I understand the desire to learn....But...

But, I'm firmly with Lake Effect and Greg (CarinaPDX) here!!

And, btw...you're going to find soldering RG-213 to / inside-of that antenna to very difficult...and not recommended!
The stiffness / unwieldy and large bend radius of RG-213, combined with the rather tight space, etc. will make for a poor-reliability connection, if you can even manage it at all....

If you desire to save this antenna for "back-up" / spare, then either replace / solder RG-58 or RG-8x...or secure / mount / solder a SO-239 directly to it....please do not attempt to solder RG-213!
(ever wonder why antennas have connectors on them, or simply RG-8x or RG-58 attached? 'cuz that's what works...





I'm going to quote (and edit some of it) myself here (from just an hour ago)....

Last month you asked about VHF antennas, and I thought we pointed you in the right direction?
I understand that you are not in the USA, but rather in the UK, so while a particular Shakespeare antenna might not be as easily available, I do recommend you look....or perhaps Glomex? (or Manta, or GAM, etc.)

Did you not find a Shakespeare? or Glomex RA109??
http://www.glomex.us/portfolio-items...c-vhf-antenna/

https://www.amazon.co.uk/Spartechnik...ct_top?ie=UTF8






2) I though we already dealt with this last month?
https://www.cruisersforum.com/forums...-235427-2.html




I do hope this helps...

Fair wind

John

Curious, why not mount the antennas on the top of the mast? They are LOS and it seems with a sailboat you have a great mounting point for antennas or radars with having a mast?

[ka4wja]

IslandInfedel,
I assume you're asking me, regarding my VHF antennas?
('cuz, I believe GTom is replacing his mastehad antenna)
But FYI, my primary VHF antenna is on the masthead!

Originally Posted by IslandInfedel

Curious, why not mount the antennas on the top of the mast? They are LOS and it seems with a sailboat you have a great mounting point for antennas or radars with having a mast?

My primary VHF antenna is mounted on my masthead, 64' off the water...
{Line-Of-Sight from 64' high is approx 9.8nm to 10nm....so, Line-Of-Sight comms between two such VHF systems, on two boats, is approx. 19.5nm to 20nm}

And, I posted a pic of this...mostly to show the coax-connector to antenna-connector and the weatherproofing of cabling/connections...




My secondary / back-up VHF antenna is mounted on the stern, at about 10' - 12' off the water....and I included a pic of this as well, also to show the weather-proofing of the cabling/connections...
{Line-Of-Sight from 12' high is approx 4.25nm to 4.5nm....so, Line-Of-Sight comms between two such VHF systems, on two boats, is approx. 8.5nm to 9nm}






2) FYI, while statistically most of our VHF Marine communications are usually fairly short-range, of 10-20 miles (and hence is done Line-Of-Sight), the fact is that VHF communications is not only line-of-sight, but rather a combination of line-of-sight and "scatter" / "tropo-scatter" (always there 24/7/365 means of over-the-horizon VHF communications)....as well as some other modes of propagation which vary and are dependent on weather / temperature inversions, etc...
But, almost all our Marine VHF comms are direct line-of-sight and "tropo-scatter"...

Please have a look here at these two threads...for much info and detail...

VHF and AIS Radiowave Propagation and VHF and AIS Radio Range
https://www.cruisersforum.com/forums...ge-149499.html


Vesper AIS SP-160 "relay/splitter" test results, lab/real world
https://www.cruisersforum.com/forums...ld-130803.html



I hope this clarifies things.

John

[IslandInfedel]

Originally Posted by ka4wja

IslandInfedel,
I assume you're asking me, regarding my VHF antennas?
('cuz, I believe GTom is replacing his mastehad antenna)
But FYI, my primary VHF antenna is on the masthead!


My primary VHF antenna is mounted on my masthead, 64' off the water...
{Line-Of-Sight from 64' high is approx 9.8nm to 10nm....so, Line-Of-Sight comms between two such VHF systems, on two boats, is approx. 19.5nm to 20nm}

And, I posted a pic of this...mostly to show the coax-connector to antenna-connector and the weatherproofing of cabling/connections...




My secondary / back-up VHF antenna is mounted on the stern, at about 10' - 12' off the water....and I included a pic of this as well, also to show the weather-proofing of the cabling/connections...
{Line-Of-Sight from 12' high is approx 4.25nm to 4.5nm....so, Line-Of-Sight comms between two such VHF systems, on two boats, is approx. 8.5nm to 9nm}






2) FYI, while statistically most of our VHF Marine communications are usually fairly short-range, of 10-20 miles (and hence is done Line-Of-Sight), the fact is that VHF communications is not only line-of-sight, but rather a combination of line-of-sight and "scatter" / "tropo-scatter" (always there 24/7/365 means of over-the-horizon VHF communications)....as well as some other modes of propagation which vary and are dependent on weather / temperature inversions, etc...
But, almost all our Marine VHF comms are direct line-of-sight and "tropo-scatter"...

Please have a look here at these two threads...for much info and detail...

VHF and AIS Radiowave Propagation and VHF and AIS Radio Range
https://www.cruisersforum.com/forums...ge-149499.html


Vesper AIS SP-160 "relay/splitter" test results, lab/real world
https://www.cruisersforum.com/forums...ld-130803.html



I hope this clarifies things.

John

thanks!

[ka4wja]

IslandInfedel,
You're welcome!

Originally Posted by IslandInfedel

thanks!

BTW, don't worry if the radio stuff / radiowave propagation, etc. seems a bit much...
'Cuz for 99.9999999999% it is...

I've just been studying, teaching, and using these things for ~ 45 years now....and few are as fanatical as I am. LOL

So, take what info you need from those postings, and smile....life is good, yes?

Fair winds

John